In my U.S. Pat. Nos. 5,577,360, 5,617,690, 5,794,396 and 6,052,961 and in my co-pending application Ser. No. 11/560,409, filed Nov. 16, 2006 and Ser. No. 12/029,017, filed Feb. 11, 2008, I disclosed various roof mounting systems which utilize tracks to mount the roofing panels such as slates to a roof. My co-pending application Ser. No. 11/950,409 and 12/029,017 include in their disclosures techniques for utilizing spacers to create an open area or air layer between vertically adjacent panels or slates. All of the details of these patents and applications are incorporated herein by reference thereto.